Juan Carlos Villarreal
Doctoral Student
Office: BioPharm 312
Voice: (860) 486-6306
Fax: (860) 486-6364
E-mail: juan.villarreal@uconn.edu, jcarlos.villarreal@gmail.com
Home page: http://hydrodictyon.eeb.uconn.edu/people/goffinet/index.html
Mailing address:
75 N. Eagleville Road, U-3043
Storrs, CT 06269
DISSERTATION RESEARCH
I am interested in the diversification and biogeographical distribution patterns of hornworts especially the Nothoceros alliance. My dissertation research is focusing in the major evolutionary events leading to the lack of sexual reproduction of the Southern Appalachian (SA) endemic and asexual hornwort Megaceros aenigmaticus . This species is the only member of the genus in North America and no sporophytes have been reported so far. In the SA region male and females live ~ 30 miles apart and male plants produce depauperate antheridia (for unknown reasons sperm cells are unable to develop functional flagella).
The first aspect of my research is unraveling the phylogenetic origin of M. aenigmaticus and its closest Neotropical relative using a multi-loci approach.
I am also testing for any cryptic sexual recombination using microsatellites and exploring the genetic consequences of the lack of sex in the population dynamics of the SA populations. In addition I will be comparing patterns of genotypic diversity between SA populations and putative conspecific and sexually reproducing populations from tropical alpine regions. Given the potential extinction threat due to the Muller's ratchet effect (accumulation of deleterious mutations), this study will have conservation and evolutionary implications (more details soon).
CURRENT INTERESTS
Systematics, anatomy, ultrastructure, molecular evolution of hornworts (Anthocerotophyta), especially Neotropical taxa. Population genetic of asexual hornwort taxa and evolution of sex in hornworts.
EDUCATION
University of Connecticut, Ecology and Evolutionary Biology, USA. Spring 2006- Doctorate’s degree
Southern Illinois University, Department of Plant Biology, Carbondale, USA. Fall 2003- Dec. 2005
Master’s degree: Ultrastructure and evolution of hornworts with emphasis in symbiotic interactions with cyanobacteria and character evolution.
Universidad de Costa Rica & Organization for Tropical Studies (OTS), Costa Rica. Jan.-Feb. 2003 Graduate course in Tropical Ecology and Conservation
University of Panamá, Bachelor’s degree in Plant Biology with Major in Bryology. 1995-2003.
Humboldt Field Research Institute & University of Maine, USA. June 2001 Field undergraduate course on biosystematics of temperate bryophytes
PUBLICATIONS
Renzaglia, K.S., J.C. Villarreal & R.J. Duff. In press. New insights into morphology, anatomy and systematics of hornworts. In Bryophyte Biology II, B. Goffinet & J. Shaw (eds).
Villarreal, J.C., G. Hässel de Menéndez & N. Salazar Allen. 2007 Nothoceros superbus (Dendrocerotaceae), a new species of hornwort from the Neotropics. The Bryologist 110: 279-285.
Duff, R.J., J.C. Villarreal, D.C. Cargill & K.S. Renzaglia. 2007. Progress and challenges toward developing a phylogeny and classification of the hornworts. The Bryologist, 110: 214-243.
Villarreal, J.C. & K.S. Renzaglia. 2006. Sporophyte structure in the neotropical hornwort Phaeomegaceros fimbriatus: implications for phylogeny, taxonomy and character evolution. International Journal of Plant Sciences 167: 413-427.
Villarreal, J.C. & K.S. Renzaglia. 2006. Structure and development of Nostoc strands in Leiosporoceros dussii (Anthocerotophyta): a novel symbiosis in land plants. American Journal of Botany 93(5): 693-705. (Cover).
Dauphin, G.; T. Pócs; J. C. Villarreal & N. Salazar Allen. 2006. Nuevos Registros de Hepáticas y Anthocerotófitas para Panamá. Tropical Bryology 27: 73-85.
Cargill, D.C.; R.J. Duff, J.C. Villarreal & K.S. Renzaglia. 2005. Generic concepts in hornworts: historical review, contemporary insights and future directions. Australian Systematic Botany 18: 7-16.
Duff, R.J.; D.C. Cargill, J.C. Villarreal & K.S. Renzaglia. 2004. Phylogenetic relationships of the hornworts based on rbcL sequence data: novel relationships and new insights. Monographs in Systematic Botany from the Missouri Botanical Garden 98: 41-58. (Book chapter)
FIELD EXPERIENCE
Panama, Costa Rica, Venezuela (Merida), Dominican Republic, Southern Appalachians.
REVIEWER FOR
The Bryologist; Cryptogamie, Bryologie-Lichénologie, Fieldiana, Journal of Experimental Botany
